1. Field of the Invention
This invention relates generally to gears and pinions and, more particularly, to apparatus and procedures for verifying parameters of an involute gear or pinion.
2. Description of the Related Art
The use of gears to transfer rotational motion from one shaft to another shaft is well-known in modern industrial practice. One type of gear is the involute gear or pinion, a gear configuration that has been widely used in the railroad industry. The involute gear is especially desirable in those applications where the center of the gear or pinion can not be maintained with precision.
In the fabrication of the gear, maintaining of precise tolerances is essential. Otherwise, the gear or pinion can develop excessive wear and can be unsuitable for operation after an unacceptably short period of time. Thus, the user of a gear or pinion will typically want to verify that the measurements of the apparatus are within specified tolerances. Similarly, it is frequently desirable to measure the gear or pinion after extended use. Unacceptable departures from the original profile can identify design problems in the apparatus utilizing the gear or pinion or defective workmanship or materials in the fabrication of the gear.
At present, complex automatic apparatus is available for testing and verifying the parameters of involute gears and pinions. The automatic apparatus involves the use of fulcrum points, linkage apparatus and ratio arms. While this apparatus provides acceptable testing and verification of the gear or pinion parameters, the apparatus is expensive and requires trained personnel for its operation. In addition, the measuring apparatus is bulky and is unsuitable for use in the field.
A need has therefore been felt for apparatus for verifying the parameters of an involute gear or pinion that is relatively inexpensive to manufacture, is simple to operate and which can be easily transported to remote locations to perform the measurements in the vicinity of the machines using the involute gear or pinion.